Evaluation of DNA damage of hydro-alcoholic and aqueous extract of Echium amoenum and Nardostachys jatamansi

Abstract

• Background: Today most of herbal medicines are marketing without any standard safety profiles. Although common assumption is that these products are nontoxic but this assumption may be incorrect and dangerous, so toxicological studies should be done for herbal drugs. According to the frequent use of Echium amoenum as immunostimulant and useful in conditions including pain, cough, sore throat and arthritis, and Nardostachys jatamansi as tranquilizer and sleep inducer and evidences of some toxicities, we assessed the probable effect of their extracts on DNA of hepG2 cells using the comet assay.
• Materials and Methods: Different concentrations of above extracts of the plants are incubated with hepG2 cells for 24 h. A mixture of cell suspension and agarose gel were put on slides, then slides were embedded in a lysing solution and were put in electrophoresis buffer (pH = 13). Then the electrophoresis procedure took place in an alkaline solution and after neutralization stage, colorization was done by ethidium bromide and comets were observed using a fluorescence microscope. At least 100 cells of each sample were evaluated and three parameters including comet length, percent of DNA in tail, and tail moment were assessed.
• Results: Both Aqueous and hydro-alcoholic extract of E. amoenum were genotoxic in the concentrations of 25 mg/ml and aqueous and hydro-alcoholic extract of N. jatamansi were genotoxic in the concentrations 5 and 10 mg/ml, respectively.
• Conclusions: Although E. amoenum and N. jatamansi are highly used in medicine, these herbs have genotoxic effects in determined concentrations and they should be used cautiously.
• Key words: Comet assay, DNA damage, Echium amoenum, Nardostachys jatamansi